Correlative relationship between biochemical activity and aggressive behaviour.

Correlative relationships were investigated between biogenic trace amines and histories of violence among offenders incarcerated in two federal penitentiaries. Plasma levels of unconjugated (U) and conjugated (C) trace acids (PAA, mHPA and pHPA) and platelet MAO activity to the substrates PE, TRYP and TA were assessed. A pilot study (N = 26) revealed a lower activity of MAO to TRYP among violent offenders. The factor analytically derived scale, Prison Disturbance, correlated with mHPA (U) .77 (p less than .001), mHPA(C) -.42 (p less than .05) and PAA (U) -.37 (p less than .10), controlling for time incarcerated. In the principal investigation (N = 103), PAA(C) (p less than .01), pHPA (U) (p less than .05) levels, and MAO activity to TRYP (p less than .05) were lower among violent offenders. Factor scores of biochemical activity produced even more significant results. However, when these results were cross validated with data from the pilot study, only minimal relationships were maintained.